Thank you for sharing and I’m sorry that your dad’s addiction is having such a bad affect on you and your mum.
I work for Icarus trust which is a charity that supports people having to deal with addiction in their family. We have people, called our Family Friends, who are trained and experienced and would understand what you are going through. If you get in touch one of them would contact you, and talking might help to answer your questions and find a way forward.
You can contact Icarus Trust on help@icarustrust.org or visit our website http://www.icarustrust.org
I hope this helps. Good luck.